HMRC has extensive powers at its disposal to enable it to check your tax position and if relevant, enquire into your Self-Assessment tax returns and tax position generally. For more serious cases including where they suspect fraud, they can open an investigation under Code of Practice 9 or investigate with a view to prosecution. Any intervention from HMRC involving a check of your tax position should be managed carefully.
Irrespective of how any errors or irregularities arose, HMRC can go back and issue assessments to recover tax for the previous 4 years. This can be extended for the previous 6 years where the behaviour that led to the error arising was the result of carelessness. HMRC can go back and collect tax liabilities for up to 20 years if you have made a ‘deliberate’ error or if you failed to notify HMRC of a liability to tax. For cases that involve offshore matters, HMRC can go back up to 12 years even where there has been no deliberate conduct.
HMRC can look back as far as:
- 20 years for deliberate cases or failure to notify
- 12 years for offshore issues
- 6 years for carelessness
- 4 years for honest mistakes
Don’t face these alone — we’ll guide you through every step.



